I did the same thing for an OSI system a few
months ago. Look in the list archive. In brief:
1) using the second set of pinouts in the comp.os.cpm
faq worked best for me.
2) build your converter on a Radio Shack Experimenters
board (part no. 276-168B). Works very well.
3) use 22disk version 1.31 or earlier. Newer versions have
timing problems with 8 inchers.